Operation Of Commands Without Data Transfer - Renesas H8S/2158 User Manual

19.5.4

Operation of Commands without Data Transfer

The broadcast and relative address commands include a number of commands that do not include
data transfer. Such commands execute the desired data transfer using command arguments and
command responses. For a command that is related to time-consuming processing such as flash
memory write/erase, the MMC indicates the data busy state via the DAT pin.
Figures 19.4 and 19.5 show examples of the command sequence for commands without data
transfer. Figure 19.6 shows the operational flow for commands without data transfer.
• Settings needed to issue a command are made.
• The START bit in CMDSTRT is set to 1 to start command transmission. Command
transmission complete can be confirmed by the command transmission end interrupt (CMDI).
• A command response is received from the MMC. If the MMC does not return the command
response, the command response is detected by the command timeout error (CTERI).
• The end of a command sequence is detected by poling the BUSY flag in CSTR or by the
command response end interrupt (CRPI).
• The end of the data busy state is detected by poling the DTBUSY flag in CSTR or by the data
busy end interrupt (DBSYI).
Section 19 Multimedia Card Interface (MCIF)
Rev. 3.00 Jan 25, 2006 page 659 of 872
REJ09B0286-0300